Our chief aim is to prepare small monodispersed resin latices which may be magnitized by an external magnetic field. The immediate application of such material - after coupling to suitable antibodies - is as NMR image contrasting agents for the early detection of cancer or cancer metastasis which are too small for detection by present methods. To achieve this goal, dispersions of magnetizable inorganic oxides in styrene are to be polymerized in the presence of varying levels of surfactants to control particle size and in the presence of one of several functional monomers to enhance capability to bond covalently to proteins. The effect of coating magnetizable particles with shells of inert polymers will be evaluated. Our specific aim under Phase I is to provide materials as indicated. Its potential for commercial development as a diagnostic tool is considered great. In addition, this project will lead to a product with a variety of particle diameters which will find other applications. There already are a number of reports on novel applications of magnetizable particles. Our products will be novel because they are not permanently magnetized, are monodispersed. They will be based on synthetic compounds which may be modified for covalent bonding to antibodies.